U.S. patent application number 12/924243 was filed with the patent office on 2011-09-29 for retractable running board/box side step.
Invention is credited to Bradley Eugene Watson.
Application Number | 20110233889 12/924243 |
Document ID | / |
Family ID | 44655491 |
Filed Date | 2011-09-29 |
United States Patent
Application |
20110233889 |
Kind Code |
A1 |
Watson; Bradley Eugene |
September 29, 2011 |
Retractable running board/box side step
Abstract
A running board assembly is provided for a motor vehicle having
a passenger cab and a box. The running board assembly includes a
housing assembly, a gear assembly disposed within the housing
assembly, a running board operably coupled to the gear assembly and
movable relative to the housing assembly between a stowed position
tucked underneath the motor vehicle, a cab entry position generally
outwardly from the motor vehicle to support a user entering or
exiting the passenger cab, and a box side step disposed generally
outwardly from the motor vehicle and rearward of the cab entry
position to provide a user with side access to the box, and a motor
operably coupled to the gear assembly for driving the gear assembly
in opposing first and second directions to move the running board
between the stowed position, the cab entry position, and the box
side step position.
Inventors: |
Watson; Bradley Eugene;
(Barrie, CA) |
Family ID: |
44655491 |
Appl. No.: |
12/924243 |
Filed: |
September 23, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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61340955 |
Mar 25, 2010 |
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Current U.S.
Class: |
280/166 |
Current CPC
Class: |
B60R 3/02 20130101 |
Class at
Publication: |
280/166 |
International
Class: |
B60R 3/02 20060101
B60R003/02 |
Claims
1. A running board assembly for a motor vehicle having a passenger
cab and a box, said running board assembly comprising: a housing
assembly; a gear assembly disposed within said housing assembly; a
running board operably coupled to said gear assembly and movable
relative to said housing assembly between a stowed position tucked
underneath the motor vehicle, a cab entry position generally
outwardly from the motor vehicle to support a user entering or
exiting the passenger cab, and a box side step position disposed
generally outwardly from the motor vehicle and rearward of said cab
entry position to provide a user with side access to the box; and a
motor operably coupled to said gear assembly for driving said gear
assembly in opposing first and second directions to move said
running board between said stowed position, said cab entry
position, and said box side step position.
2. The running board assembly as set forth in claim 2 including a
drive arm operably coupled to said gear assembly and fixedly
secured to said running board for pivotally moving said running
board between said stowed, cab entry, and box side step
positions.
3. The running board assembly as set forth in claim 2 wherein said
gear assembly includes a rotatable worm drive shaft member operably
coupled to said motor.
4. The running board assembly as set forth in claim 3 wherein said
housing assembly includes a rotatably drive shaft operably coupled
to said worm drive shaft member and fixedly secured to said drive
arm.
5. The running board assembly as set forth in claim 4 wherein said
gear assembly includes a worm member fixedly mounted along said
worm drive shaft member.
6. The running board assembly as set forth in claim 5 including a
driven gear fixedly mounted to said drive shaft and in meshing
engagement with said worm member.
7. The running board assembly as set forth in claim 1 including an
electronic control unit operably coupled to said motor and
electronically controlling operation thereof.
8. The running board assembly as set forth in claim 7 wherein said
electronic control unit is programmed to turn off said motor after
a predetermined number of armature revolutions to stop said running
board in said cab entry position.
9. A running board assembly for a motor vehicle having a passenger
cab and a box, said running board assembly comprising: a housing
assembly; a gear assembly disposed within said housing assembly; a
running board operably coupled to said gear assembly and movable
relative to said housing assembly between a stowed position tucked
underneath the motor vehicle, a cab entry position generally
outwardly from the motor vehicle to support a user entering or
exiting the passenger cab, and a box side step position disposed
generally outwardly from the motor vehicle and rearward of said cab
entry position to provide a user with side access to the box; a
drive arm fixedly secured to said running board and operably
coupled to said gear assembly, said drive arm including a first
stop engageable with said running board to stop said running board
in said stowed position and a second stop engageable with said
running board to stop said running board in said box step side
position; a motor operably coupled to said gear assembly for
driving said drive arm to pivotally move said running board between
said stowed position, said cab entry position, and said box step
side position; and an electronic control unit operably coupled to
said motor and programmed to turn off said motor after a
predetermined number of armature revolutions to stop said running
board in said cab entry position.
10. A running board assembly as set forth in claim 9 including a
switch member transmitting a signal to said electronic control unit
to move said running board between said stowed and cab entry
positions upon the opening and closing of a motor vehicle door.
11. A running board assembly as set forth in claim 9 including a
switch member electronically connected to said electronic control
unit and providing a signal thereto for moving said running board
into and out of said box side step position.
12. A running board assembly for a motor vehicle having a passenger
cab and a box, said running board assembly comprising: a mounting
bracket adapted for attachment to the motor vehicle; a running
board movable relative to said mounting bracket between a stowed
position tucked underneath the motor vehicle, a cab entry position
disposed generally outwardly from the motor vehicle to support a
user entering or exiting the passenger cab, and a box side step
position disposed generally outwardly from the motor vehicle and
generally rearward to said cab entry position to provide a user
with side access to the box; a motor operably coupled to said
running board for driving movement thereof; an electronic control
unit electronically connected to said motor, said electronic
control unit selectively programmable to turn off said motor to
stop said running board in said cab entry position; and a housing
assembly including a rotatable worm member operably coupled to said
motor, said housing assembly including a zero backlash gear
assembly having a lower gear fixedly mounted along a rotatable
drive shaft and in meshing engagement with said worm member, said
zero backlash gear assembly also including an upper gear freely
mounted on said shaft for movement relative to said lower gear,
said zero backlash gear assembly including a biasing member biasing
said upper gear into engagement with said worm member to eliminate
backlash of said running board when said running board is in said
cab entry position.
13. A running board assembly as set forth in claim 12 including a
switch member electronically connected to said electronic control
unit and providing a signal thereto for moving said running board
into and out of said box side step position.
14. The running board assembly as set forth in claim 12 including a
drive arm operably coupled to said gear assembly and fixedly
secured to said running board for pivotally moving said running
board between said stowed, cab entry, and box side step
positions.
15. The running board assembly as set forth in claim 12 wherein
said upper gear defines a clearance hole for receiving a pin
mounted on said lower gear therethrough to allow rotation of said
upper gear relative to said lower gear.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional
Application No. 61/340,955, filed Mar. 25, 2010.
BACKGROUND
[0002] The invention relates to a running board assembly for a
motor vehicle. More particularly, the invention relates to a
running board assembly including a running board movable between a
stowed position, a cab entry position, and a box side step
position.
SUMMARY
[0003] According to one aspect of the invention, a running board
assembly is provided for a motor vehicle having a passenger cab and
a box. The running board assembly includes a housing assembly, a
gear assembly disposed within the housing assembly, a running board
operably coupled to the gear assembly and movable relative to the
housing assembly between a stowed position tucked underneath the
motor vehicle, a cab entry position generally outwardly from the
motor vehicle to support a user entering or exiting the passenger
cab, and a box side step position disposed generally outwardly from
the motor vehicle and rearward of the cab entry position to provide
a user with side access to the box, and a motor operably coupled to
the gear assembly for driving the gear assembly in opposing first
and second directions to move the running board between the stowed
position, the cab entry position, and the box side step
position.
[0004] According to another aspect of the invention, a running
board assembly for a motor vehicle having a passenger cab and a box
includes a housing assembly, a gear assembly disposed within the
housing assembly, and a running board operably coupled to the gear
assembly and movable relative to the housing assembly between a
stowed position tucked underneath the motor vehicle, a cab entry
position generally outwardly from the motor vehicle to support a
user entering or exiting the passenger cab, and a box side step
position disposed generally outwardly from the motor vehicle and
rearward of the cab entry position to provide a user with side
access to the box. The running board assembly also includes a drive
arm fixedly secured to the running board and operably coupled to
the gear assembly, said drive arm including a first stop engageable
with the running board to stop the running board in the stowed
position and a second stop engageable with the running board to
stop the running board in the box step side position. The running
board assembly further includes a motor operably coupled to the
gear assembly for driving the drive arm to pivotally move the
running board between the stowed position, the cab entry position,
and the box step side position, and an electronic control unit
operably coupled to the motor and programmed to turn off the motor
after a predetermined number of armature revolutions to stop the
running board in the cab entry position.
[0005] According to yet another aspect of the invention, a running
board assembly for a motor vehicle includes a mounting bracket
adapted for attachment to the motor vehicle, a running board
movable relative to the mounting bracket between a stowed position
tucked underneath the motor vehicle, a cab entry position disposed
generally outwardly from the motor vehicle, and a box side step
position disposed generally outwardly from the motor vehicle and
generally rearward to the cab entry position, a motor operably
coupled to the running board for driving movement thereof, and an
electronic control unit electronically connected to the motor and
programmed to turn off said motor when said running board reaches
said cab entry position. The running board assembly also includes a
housing assembly including a worm member operably coupled to the
motor. The housing assembly includes a zero backlash gear assembly
having a lower gear fixedly mounted along a shaft and an upper gear
freely mounted on the shaft for movement relative thereto. The zero
backlash gear assembly includes a biasing member biasing the upper
gear into engagement with the worm member to eliminate backlash of
the running board when the running board is in the cab entry
position.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The invention will be readily appreciated as the same
becomes better understood by reference to the following detailed
description when considered in connection with the accompanying
drawings wherein:
[0007] FIG. 1 is a perspective view of one embodiment of a running
board assembly including a running board;
[0008] FIG. 2 is a side view of a motor vehicle including the
running board in a stowed position;
[0009] FIG. 3 is a side view of the motor vehicle including the
running board in a cab entry position;
[0010] FIG. 4 is a side view of the motor vehicle including the
running board in a box side step position;
[0011] FIG. 5 is a perspective view of a housing assembly, a drive
arm, and a motor assembly of the running board assembly;
[0012] FIG. 6 is a perspective view of the housing assembly and the
drive arm wherein a cover structure and a main housing structure
have been removed to show a worm member in meshing engagement with
a driven gear;
[0013] FIG. 7 is a perspective view of the drive arm of the running
board assembly secured to a drive shaft;
[0014] FIG. 8 is a perspective view of the running board assembly
including the running board in the stowed position;
[0015] FIG. 9 is a perspective view of the running board assembly
including the running board in the cab entry position;
[0016] FIG. 10 is a perspective view of the running board assembly
including the running board in the box side step position;
[0017] FIG. 11 is a top view of the running board assembly showing
the running board in the stowed, cab entry, and box side step
positions;
[0018] FIG. 12 is a fragmentary rear perspective view of the motor
vehicle including an end cap switch, a body-mounted switch, and a
key fob for activating movement of the running board into and out
of the box side step position; and
[0019] FIG. 13 is a perspective view of a zero backlash gear
assembly operably coupled to the worm member in a running board
assembly according to another embodiment.
DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS
[0020] Referring to FIG. 1, a running board assembly, generally
shown at 10, in one embodiment includes a running board 12, a
housing assembly 14, a drive arm 16, an idler arm 18, a gear
assembly 20, a motor assembly 22, an electronic control unit 24,
and a mounting bracket 26. The mounting bracket 26 is adapted for
attachment to a frame of a motor vehicle 28.
[0021] The running board 12 has a top wall 30 providing a tread
surface 32 therealong. The running board 12 is connected to the
drive 16 and idler 18 arms at pivots 34. The pivots 34 are arranged
generally vertically and include a shaft extending through a bore
in the end of the drive 16 and idler 18 arms and retained in place
by a retaining ring. The idler arm 18 is mounted to a hub structure
36 which pivotally secures the idler arm 18 to a rear bracket 38.
The rear bracket 38 is mounted to the mounting bracket 26 which is
attached to the frame of the motor vehicle 28. It is appreciated
that although a single idler arm 18 is shown, the running board
assembly 10 in another embodiment may include more than one idler
arm 18.
[0022] The drive 16 and idler 18 arms form a parallel linkage which
pivotally couples the running board 12 to a frame of the motor
vehicle 28 for movement between a stowed position, as shown in FIG.
2, a cab entry position, as shown in FIG. 3, and a box side step
position, as shown in FIG. 4. In the stowed position, the running
board 12 is generally tucked underneath the motor vehicle 28 so as
to be somewhat hidden from view and to provide a cleaner, more
integrated look to the motor vehicle 28. In the cab entry position,
the running board 12 extends generally outwardly from the motor
vehicle 28 to assist users entering or exiting a passenger cab 40.
And in the box side step position, the running board 12 extends
generally outwardly from the motor vehicle 28 and is disposed
rearward as compared to the cab entry position in order to allow
users side access to a box 41 of the motor vehicle 28. The running
board 12 provides a more useful step surface with improved step
length for box access as compared to a separate frame mounted side
step.
[0023] Referring to FIGS. 5 through 7, the housing assembly 14
includes a cover structure 42 and a main housing structure 44. The
cover structure 42 is secured to the main housing structure 44 by a
plurality of cover screws 46. The cover structure 42 and the main
housing structure 44 define an internal chamber within the housing
assembly 14. The housing assembly 14 also includes a gear housing
portion 48, and a rear bracket 50 which is secured to the mounting
bracket 26.
[0024] The gear assembly 20 includes a worm drive shaft member 52
disposed within the gear housing portion 48 and rotatable relative
thereto. The worm drive shaft member 52 is operably coupled to the
motor assembly 18. A worm member 54 is fixedly mounted along the
worm drive shaft member 52 for rotation therewith. The worm member
54 can be of any conventional configuration. A plurality of threads
56 is defined on an exterior cylindrical surface of the worm member
54.
[0025] The gear assembly 20 also includes a driven gear 58 in
meshing engagement with the worm member 54. The driven gear 58 is
fixedly supported along a drive shaft 60 proximate an upper end 62
thereof. Thus, the rotation of the worm member 54 will cause
rotation of the drive shaft 60 via the driven gear 58. A lower end
64 of the drive shaft 60 is fixedly retained within a bore 66
formed in the drive arm 16. Thus, the rotation of the drive shaft
60 drives pivotal movement of the drive arm 16.
[0026] The drive arm 16 includes a first end 68 coupled to the
drive shaft 60 and an opposing second end 70 coupled to the running
board 12. The drive arm 16 includes a stow stop 72 and an end stop
74 formed at a location between the first 68 and second 70 ends.
The running board 12 abuts the stow stop 72 to stop further
movement of the running board 12 when the running board 12 has
reached the stowed position. The running board 12 abuts the end
stop 74 to stop further movement of the running board 12 when the
running board 12 has reached the box side step position. In one
embodiment, the stow 72 and end 74 stops include bumpers 75 which
may be formed from urethane or a like material.
[0027] The motor assembly 18 includes a casing structure 76 which
includes a conventional position sensing and encoding motor 78 that
rotates a motor shaft (not shown) in opposing first and second
directions. The motor assembly 18 is secured to the gear assembly
20. More particularly, the motor shaft extends into the gear
housing portion 48 and is fixedly secured to the worm drive shaft
member 52 such that activation of the motor 78 will rotate the worm
drive shaft member 52 in the same direction. The casing structure
76 is secured to the gear housing portion 48 by a plurality of
fasteners 82. It is appreciated that the casing structure 76 may in
one embodiment be considered part of the housing assembly 12 as the
housing assembly 12 maintains the gear and motor components sealed
from the external environment.
[0028] Referring back to FIG. 1, the electronic control unit 24
electronically controls the motor assembly 22 to effect movement of
the running board 12 between the stowed, cab entry, and box side
step positions. The electronic control unit 24 is mounted within
the motor vehicle 28 at a location remote from the housing assembly
14. The electronic control unit 24 is electrically connected to the
motor assembly 22, to a wiring harness of the motor vehicle 28, and
to a switch member 84 incorporated into a door 86 of the motor
vehicle 28. In another embodiment, the electronic control unit 24
may be physically mounted to the housing assembly 14 or to the
motor assembly 22, and electronically connected to the motor
assembly 22.
[0029] The switch member 84 in one embodiment is a door-actuated
switch member that is part of the motor vehicle 28 and is
controlled in a conventional manner by the door 86. The wiring
harness supplies the electrical power from the vehicle electrical
system to the electronic control unit 24 of the running board
assembly 10 through electrical wire members 88. The structure and
operation of a conventional switch member which is operationally
interconnected to the vehicle door 86 is well known. It is
understood by one skilled in the art that such switch members are
toggled by the opening or the closing of the vehicle door 86
associated therewith to open and close an electrical circuit. Wire
members 90 provide electrical connection between the electronic
control unit 24 and the motor assembly 22 so that the electronic
control unit 24 can supply electrical power from the vehicle
electrical system to the motor assembly 22 to effect the
bi-directional operation thereof. Wire members 92 provide
electrical communication between the electronic control unit 24 and
the door-actuated switch member 84.
[0030] In one embodiment, the switch member 84 is a door ajar
switch in a door latch. The motor assembly 22 is energized to move
the running board 12 from the stowed position to the cab entry
position upon receiving a signal from the door ajar switch
indicating that the vehicle door 86 has been opened. The motor
assembly 22 is energized to return the running board 12 to the
stowed position upon receiving a signal from the door ajar switch
indicating that the vehicle door 86 has been closed.
[0031] In operation, starting with the running board 12 in the
stowed position shown in FIG. 8, when the vehicle door 86 is
unlatched and pivoted outwardly from a closed position to an open
position, the switch member 84 associated with the vehicle door 86
is activated and sends a control signal to the electronic control
unit 24. The electronic control unit 24 in response to the control
signal supplies an appropriate voltage to the motor assembly 22 to
cause the motor assembly 22 to begin rotational movement in a first
rotational direction which will pivot the drive arm 16 to move the
running board 12 to the cab entry position. Specifically, the motor
78 rotates the worm drive shaft member 52 in a first rotational
direction which in turn rotates the worm member 54. The worm member
54 rotates the driven gear 58. The drive shaft 60 rotates with the
driven gear 58 and causes the drive arm 16 to pivot outwardly away
from the motor vehicle 28 to move the running board 12 to the cab
entry position. The particular location of the running board 12 in
the cab entry position is electronically controlled by the motor
78. The electronic control unit 24 is programmed to stop the motor
78 after a predetermined number of armature revolution counts. As a
result, the exact location of the running board 12 in the cab entry
position may vary depending upon when the motor 78 is programmed to
stop. When the electronic control unit 24 senses that the running
board 12 has reached the cab entry position, the electronic control
unit 24 turns off the motor 78.
[0032] The running board 12 is retained in the cab entry position
after the motor assembly 22 is shut off as a result of the meshing
engagement between the worm member 54 and the driven gear 58, as it
is known that the worm member 54 will not be back-driven by the
driven gear 58. Thus, the worm member 54 will resist an external
force applied to the drive arm 16 in a direction away from the cab
entry position and towards the stowed position as a result of the
meshing engagement.
[0033] The running board 12 remains in the cab entry position until
the door 86 of the motor vehicle 28 is returned to the closed
position. When the door 86 is pivoted inwardly from the open
position to the closed position, the switch member 84 associated
therewith is activated and sends a signal to the electronic control
unit 24. The electronic control unit 24 in response to the signal
supplies an appropriate voltage to the motor assembly 22 which will
pivot the drive arm 16 to move the running board 12 to the stowed
position. Specifically, the motor shaft 80 of the motor assembly 22
rotates the worm drive shaft member 52 in a second rotational
direction which in turn rotates the worm member 54. The worm member
54 rotates the driven gear 58. The drive shaft 60 rotates with the
driven gear 58 and drives the drive arm 16 to pivot inwardly
towards the motor vehicle 28 to move the running board 12 to the
stowed position. The stow stop 72 and the electronic control unit
24 are used to turn off the motor 78 of the motor assembly 22. The
running board 12 will continue to move towards the stowed position
until the running board 12 abuts the stow stop 72 on the drive arm
60. A current spike is generated in the motor assembly 22 as a
result of the motor assembly 22 meeting a resistance to movement
when the running board 12 hits the stow stop 72. The current spike
will be instantaneously detected by the electronic control unit 24.
In response to the current spike, the electronic control unit 24
turns off the motor 78.
[0034] Referring to FIG. 12, the motor vehicle 28 may include an
input member such as a body-mounted switch 96, an end cap switch
98, or a key fob (not shown) to initiate movement of the running
board 12 into and out of the box side step position. The
body-mounted switch 96 and the end cap switch 98 may be
electrically connected to the electronic control unit 24 by wire
members 100 or by a wireless connection. The body-mounted switch 96
is easily accessible by hand and the end cap switch 98 may be
accessed by a user's foot. Thus, the running board 12 may be
hand-operated, or foot-operated if hands-free operation of the
running board 12 is desired. The running board 12 may be moved into
the box side step position from either the stowed position or the
cab entry position. Upon activation of one of the switches 96, 98
or the key fob, a signal is sent to the electronic control unit 24.
The electronic control unit 24 in response to the signal supplies
an appropriate voltage to the motor assembly 22 to cause rotational
movement in a first direction which will pivot the drive arm 16 to
move the running board 12 to the box side step position. The
running board 12 will continue to move towards the box side step
position until the running board 12 abuts the end stop 74 on the
drive arm 16. A current spike is generated in the motor assembly 22
as a result of the motor assembly 22 meeting a resistance to
movement when the running board 12 hits the end stop 74. The
current spike will be instantaneously detected by the electronic
control unit 24. In response to the current spike, the electronic
control unit 24 turns off the motor 78.
[0035] To move the running board 12 out of the box side step
position and into the stowed position, the body-mounted switch 96,
the end cap switch 98, or the key fob is activated which sends a
signal to the electronic control unit 24. The electronic control
unit 24 in response to the signal supplies an appropriate voltage
to the motor assembly 22 to cause rotational movement in a second
rotational direction which will pivot the drive arm 16 to move the
running board 12 to the stowed position. Specifically, the motor 78
rotates the worm drive shaft member 52 in a second rotational
direction which in turn rotates the worm member 54. The worm member
54 rotates the driven gear 58. The drive shaft 60 rotates with the
driven gear 58 and drives the drive arm 16 to pivot inwardly
towards the motor vehicle 28 to move the running board 12 to the
stowed position. The running board 12 reaches the stowed position
when the running board 12 abuts the stow stop 72 on the drive arm
16. A current spike is generated in the motor assembly 22 as a
result of the motor assembly 22 meeting a resistance to movement
when the running board 12 hits the stow stop 72. The current spike
will be instantaneously detected by the electronic control unit 24.
In response to the current spike, the electronic control unit 24
turns off the motor 78. It is further contemplated that in the
alternative the running board 12 may be moved from the box side
step position to the cab entry position.
[0036] Referring to FIG. 13, wherein like primed reference numerals
represent similar elements as those set forth above, the running
board assembly 10' according to a second embodiment includes a zero
backlash gear assembly, generally indicated at 102, operably
coupled between the worm member 54' and the drive shaft 60' to
eliminate backlash in the running board assembly 10' when the
running board assembly 10' is in the cab entry position. The zero
backlash gear assembly 102 includes a lower gear 104 fixedly
mounted along the drive shaft 60' for rotation therewith, and an
upper gear 106 freely supported along the drive shaft 60' for
rotation relative to the lower gear 104. The upper gear 106 defines
at least one clearance hole 108 for receiving a pin 110 of the
lower gear 104 therethrough. The clearance hole 108 is sized to
allow rotation of the upper gear 106 relative to the lower gear
104. The upper gear 106 includes biasing members 112 each extending
between a pair of support members 114. It is appreciated that the
particular number of biasing members 112 may vary. The biasing
members 112 preload the upper gear 106 into rotation relative to
the lower gear 104. When the running board 12' reaches the cab
entry position, the zero backlash gear assembly 102 prevents
backlash in the system as teeth 116 on the lower gear 104 engage
one side of teeth 118 on the worm member 54' and teeth 120 on the
upper gear 106 engage the other side of the teeth 118 on the worm
member 54'. As a result, when a user steps on the running board 12
in the cab entry position, the user will not feel any variation in
the running board 12 and the user will have a better tactile feel
on the running board 12.
[0037] The invention has been described in an illustrative manner.
It is to be understood that the terminology, which has been used,
is intended to be in the nature of words of description rather than
of limitation. Many modifications and variations of the invention
are possible in light of the above teachings. Therefore, within the
scope of the appended claims, the invention may be practiced other
than as specifically described.
* * * * *